Dry-type Current Transformers

Detailed Product Description

1 Possessing those advantages of light structure, oil-free, gas-free, porcelain-free, fire-proof and explosion-proof etc, it has been serviced in current measurement and relay protection in power system with the rated voltage of 220 kV.

2 Technical Parameters for LGB-220W (1~3)  Current Transformers

2.1  Rated voltage  220 kV

2.2  Highest voltage for equipment  252 kV

2.3  Rated primary current  300 A~4000 A

2.4  Rated secondary current  5 A or 1A

2.5  Rated frequency  50 (60) Hz

2.6  Rated output  20~50 VA (If any other rated output required, We can satisfy it.)

2.7  Accuracy class and accuracy classes combination

Steady accuracy classes are 0.2S, 0.2, 0.5S, 0.5, 5P, 10P, PR and PX; transient accuracy classes are TPS, TPX, TPY and TPZ. There are 1~6 pcs secondary windings in a CT.

2.8  Instrument security factor (FS) of measuring class  5 or 10

2.9  Accuracy limit factor (ALF) of protective class  5, 10, 15, 20, 30 or 40

2.10 Rated continuous thermal current I_cth  1.2I_n

2.11 For rated short-time thermal current I_th (rms) and rated dynamic current I_dyn (peak), please see Table 1.

Table 1

Primary Current (A)	300~800	1000~2500	3000~4000
Rated Short-time Thermal Current (rms) (kA), 3s	31.5	42	50
Rated Dynamic Current (Peak) (kA)	80	105	125

2.12  Arcing distance ≥2010 (mm)

2.13  Creepage distance of outer insulation please see Table 2

Table 2

Pollution Protection Class	Class II	Class III	Class IV
Creepage Distancemm	≥5040	≥6300	≥7812